U.S. patent application number 16/584997 was filed with the patent office on 2020-01-23 for monitoring system and oxygen measurement system.
This patent application is currently assigned to TERUMO KABUSHIKI KAISHA. The applicant listed for this patent is TERUMO KABUSHIKI KAISHA. Invention is credited to Satoru SUEHARA, Akihiro TAKAHASHI.
Application Number | 20200022638 16/584997 |
Document ID | / |
Family ID | 63677196 |
Filed Date | 2020-01-23 |
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United States Patent
Application |
20200022638 |
Kind Code |
A1 |
SUEHARA; Satoru ; et
al. |
January 23, 2020 |
MONITORING SYSTEM AND OXYGEN MEASUREMENT SYSTEM
Abstract
A monitoring system which constitutes an oxygen measurement
system includes: an oxygen partial pressure calculation unit that
calculates an oxygen partial pressure in urine based on an output
signal from the oxygen measurement device; a monitor that displays
the oxygen partial pressure calculated by the oxygen partial
pressure calculation unit; and a display control unit that changes
a format of display of the oxygen partial pressure displayed by the
monitor according to the flow rate of urine acquired based on the
output signal from the oxygen measurement device.
Inventors: |
SUEHARA; Satoru; (Kanagawa,
JP) ; TAKAHASHI; Akihiro; (Kanagawa, JP) |
|
Applicant: |
Name |
City |
State |
Country |
Type |
TERUMO KABUSHIKI KAISHA |
Tokyo |
|
JP |
|
|
Assignee: |
TERUMO KABUSHIKI KAISHA
Tokyo
JP
|
Family ID: |
63677196 |
Appl. No.: |
16/584997 |
Filed: |
September 27, 2019 |
Related U.S. Patent Documents
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Application
Number |
Filing Date |
Patent Number |
|
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PCT/JP2018/009546 |
Mar 12, 2018 |
|
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16584997 |
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Current U.S.
Class: |
1/1 |
Current CPC
Class: |
A61B 5/14556 20130101;
A61B 5/7271 20130101; A61B 5/01 20130101; A61B 5/1459 20130101;
A61B 5/6853 20130101; A61B 5/6852 20130101; A61B 5/743 20130101;
A61B 5/208 20130101; A61B 5/204 20130101; A61B 5/14507 20130101;
A61B 5/742 20130101; A61B 5/201 20130101 |
International
Class: |
A61B 5/20 20060101
A61B005/20; A61B 5/00 20060101 A61B005/00; A61B 5/145 20060101
A61B005/145 |
Foreign Application Data
Date |
Code |
Application Number |
Mar 30, 2017 |
JP |
2017-066659 |
Claims
1. An oxygen measurement system comprising: a urethral catheter
that includes a urine flow lumen in which urine circulates; an
oxygen sensor that is mounted along the urine flow lumen in the
urethral catheter and that outputs an output signal used to
calculate an oxygen partial pressure in the urine circulating in
the urine flow lumen of the urethral catheter; a flow rate sensor
that is mounted along the urine flow lumen in the urethral catheter
and that outputs an output signal used to calculate a flow rate of
the urine circulating in the urine flow lumen of the urethral
catheter; an oxygen partial pressure calculation unit that
calculates the oxygen partial pressure in the urine circulating in
the urine flow lumen of the urethral catheter based on the output
signal output from the oxygen sensor; a flow rate calculation unit
that calculates a flow rate of the urine circulating in the urine
flow lumen of the urethral catheter based on the output signal
output from the flow rate sensor; a monitor that displays the
oxygen partial pressure calculated by the oxygen partial pressure
calculation unit; and a display control unit that is connected to
the monitor and that changes a format of a display of the oxygen
partial pressure on the monitor so that the format of the display
of the oxygen partial pressure on the monitor varies based on the
flow rate of the urine.
2. The oxygen measurement system according to claim 1, further
comprising: a flow rate determination unit that determines whether
or not the flow rate of the urine acquired based on the output
signal from the flow rate sensor is equal to or more than a
predetermined value; and the display control unit controlling the
format of the display of the oxygen partial pressure on the monitor
so that the oxygen partial pressure is displayed on the monitor in
a first display format when the flow rate determination unit
determines that the flow rate of the urine is equal to or higher
than the predetermined value, and controlling the format of the
display of the oxygen partial pressure on the monitor so that the
oxygen partial pressure is displayed on the monitor in a second
display format visually different from the first display format
when the flow rate determination unit determines that the flow rate
of the urine is less than the predetermined value.
3. The oxygen measurement system according to claim 1, further
comprising: a flow rate determination unit that determines whether
or not the flow rate of the urine acquired based on the output
signal from the flow rate sensor is equal to or more than a
predetermined value; and the display control unit controlling the
format of the display of the oxygen partial pressure so that the
oxygen partial pressure is displayed on the monitor when the flow
rate determination unit determines that the flow rate of urine is
equal to or higher than the predetermined value, and controlling
the format of the display of the oxygen partial pressure so that
the oxygen partial pressure is not displayed on the monitor when
the flow rate determination unit determines that the flow rate of
urine is less than the predetermined value.
4. The oxygen measurement system according to claim 1, wherein the
display control unit controls the format of the display of the
oxygen partial pressure on the monitor so that the monitor displays
a graph indicating a temporal change of the oxygen partial
pressure.
5. The oxygen measurement system according to claim 1, wherein the
oxygen partial pressure calculation unit calculates the oxygen
partial pressure in urine corrected by temperature of the urine
acquired based on an output signal from a further sensor of the
oxygen measurement device.
6. The oxygen measurement system according to claim 1, further
comprising: a urine volume calculation unit connected to the flow
rate sensor to receive an output signal from the flow rate sensor
and to calculate, for display on the monitor, a urine volume based
on the output signal from the flow rate sensor; a urine volume
determination unit that determines whether or not the urine volume
calculated by the urine volume calculation unit matches a
predetermined urine volume condition; and the display control unit
displaying the predetermined urine volume condition on the monitor
when the urine volume determination unit determines that the urine
volume matches the urine volume condition.
7. A monitoring system which is connectable to an oxygen
measurement device that includes sensors to be exposed to urine and
which operates to calculate an oxygen partial pressure in urine and
a flow rate of urine, the monitoring system comprising: an oxygen
partial pressure calculation unit connected to a first one of the
sensors of the oxygen measurement device when the monitoring system
is connected to the oxygen measurement device to receive an output
signal from the first sensor and to calculate, for display on the
monitor, an oxygen partial pressure in the urine based on the
output signal from the first sensor of the oxygen measurement
device; a flow rate calculation unit connected to a second one of
the sensors of the oxygen measurement device when the monitoring
system is connected to the oxygen measurement device to receive an
output signal from the second sensor and to calculate a flow rate
of the urine based on the output signal from the second sensor of
the oxygen measurement device; and a display control unit that is
connected to a monitor during operation of the monitoring system
and that controls a format of a display of the oxygen partial
pressure on the monitor so that the format of the display of the
oxygen partial pressure on the monitor varies based on the
calculated flow rate of urine, to thereby allow a user of the
monitoring system to confirm whether or not the oxygen partial
pressure is an oxygen partial pressure acquired in a state that
appropriately reflects a state of the kidneys.
8. The monitoring system according to claim 7, further comprising:
a flow rate determination unit that determines whether or not the
flow rate of the urine acquired based on the output signal from the
second sensor of the oxygen measurement device is equal to or more
than a predetermined value, the display control unit controlling
the format of the display of the oxygen partial pressure so that
the oxygen partial pressure is displayed on the monitor in a first
display format when the flow rate determination unit determines
that the flow rate of the urine is equal to or higher than the
predetermined value, and controlling the format of the display of
the oxygen partial pressure so that the oxygen partial pressure is
displayed on the monitor in a second display format visually
different from the first display format when the flow rate
determination unit determines that the flow rate of the urine is
less than the predetermined value.
9. The monitoring system according to claim 7, further comprising:
a flow rate determination unit that determines whether or not the
flow rate of the urine acquired based on the output signal from the
first sensor of the oxygen measurement device is equal to or more
than a predetermined value, wherein the display control unit
controlling the format of the display of the oxygen partial
pressure so that the oxygen partial pressure is displayed on the
monitor when the flow rate determination unit determines that the
flow rate of urine is equal to or higher than the predetermined
value, and controlling the format of the display of the oxygen
partial pressure so that the oxygen partial pressure is not
displayed on the monitor when the flow rate determination unit
determines that the flow rate of urine is less than the
predetermined value.
10. The monitoring system according to claim 7, wherein the display
control unit controls the format of the display of the oxygen
partial pressure on the monitor so that the monitor displays a
graph indicating a temporal change of the oxygen partial
pressure.
11. The monitoring system according to claim 7, wherein the oxygen
partial pressure calculation unit calculates the oxygen partial
pressure in urine corrected by temperature of the urine acquired
based on an output signal from a further sensor of the oxygen
measurement device.
12. The monitoring system according to claim 7, further comprising:
a urine volume calculation unit connected to the second one of the
sensors of the oxygen measurement device when the monitoring system
is connected to the oxygen measurement device to receive an output
signal from the second sensor and to calculate, for display on the
monitor, a urine volume based on the output signal from the second
sensor of the oxygen measurement device ; and a urine volume
determination unit that determines whether or not the urine volume
calculated by the urine volume calculation unit matches a
predetermined urine volume condition, the display control unit
displaying the predetermined urine volume condition on the monitor
when the urine volume determination unit determines that the urine
volume matches the urine volume condition.
13. A method comprising: positioning a distal portion of an
elongated urethral catheter in a bladder of a living body, the
elongated urethral catheter including a lumen extending along the
elongated urethral catheter; introducing urine from the bladder of
the living body into the lumen of the elongated urethral catheter;
calculating an oxygen partial pressure in the urine in the lumen of
the elongated urethral catheter based on an output signal of a
first sensor that is contacted by the urine in the lumen of the
elongated urethral catheter; calculating a flow rate of the urine
in the lumen of the elongated urethral catheter based on an output
signal from a second sensor that is contacted by the urine in the
lumen of the elongated urethral catheter; and controlling display
of the calculated oxygen partial pressure on the monitor, the
controlling of the display of the calculated oxygen partial
pressure comprising varying a format of the display of the oxygen
partial pressure on the monitor based on the calculated flow rate
of the urine.
14. The method according to claim 13, wherein the displaying of the
calculated oxygen partial pressure comprises simultaneously
displaying two calculated oxygen partial pressures on the monitor
using a different format of display so that a user can visually
distinguish the two calculated oxygen partial pressures.
15. The method according to claim 13, further comprising:
determining whether or not the calculated flow rate of the urine in
the lumen of the elongated urethral catheter is at least equal to a
predetermined value; the controlling of the display of the
calculated oxygen partial pressure on the monitor comprising
displaying the calculated oxygen partial pressure on the monitor in
a first display format when the flow rate determination unit
determines that the flow rate of the urine is at least equal to the
predetermined value; and the controlling of the display of the
calculated oxygen partial pressure on the monitor comprising
displaying the calculated oxygen partial pressure on the monitor in
a second display format visually different from the first display
format when the flow rate determination unit determines that the
flow rate of the urine is less than the predetermined value.
16. The method according to claim 13, further comprising:
determining whether or not the calculated flow rate of the urine in
the lumen of the elongated urethral catheter is at least equal to a
predetermined value; the controlling of the display of the
calculated oxygen partial pressure on the monitor comprising
displaying the calculated oxygen partial pressure on the monitor
when the flow rate determination unit determines that the flow rate
of urine is at least equal to the predetermined value; and the
controlling of the display of the calculated oxygen partial
pressure on the monitor comprising not displaying the calculated
oxygen partial pressure on the monitor when the flow rate
determination unit determines that the flow rate of urine is less
than the predetermined value.
17. The method according to claim 13, wherein the controlling of
the display of the calculated oxygen partial pressure comprises
controlling the format of the display of the oxygen partial
pressure on the monitor so that the monitor displays a graph
indicating a temporal change of the oxygen partial pressure.
18. The method according to claim 13, further comprising
determining a temperature of the urine in the lumen of the
elongated urethral catheter, and wherein the calculating of the
oxygen partial pressure in the urine in the lumen of the elongated
urethral catheter comprises calculating the oxygen partial pressure
that is corrected by the temperature of the urine.
19. The method according to claim 13, further comprising:
calculating a urine volume based on the output signal from the
second sensor; determining whether or not the calculated urine
volume matches a predetermined urine volume condition; and
displaying the predetermined urine volume condition on the monitor
when the urine volume is determined to match the urine volume
condition.
Description
CROSS-REFERENCES TO RELATED APPLICATIONS
[0001] This application is a continuation of International
Application No. PCT/JP2018/009546 filed on Mar. 12, 2019, which
claims priority to Japanese Patent Application No. 2017-066659
filed on Mar. 30, 2019, the entire content of which is incorporated
herein by reference.
FIELD OF THE INVENTION
[0002] The present invention generally relates to a monitoring
system provided in a urethral catheter, and an oxygen measurement
system.
BACKGROUND DISCUSSION
[0003] Japanese Patent No. 2739880 discloses an example of an
oxygen measurement device in which an oxygen sensor is inserted
into the bladder and indwelled through the urine flow lumen of a
urethral catheter. This oxygen measurement device is a device that
detects oxygen partial pressure in the epithelial wall and monitors
it by leading-out an oxygen sensor main body of an oxygen sensor
from a urethral catheter port formed at a distal portion of the
urethral catheter, and bringing the oxygen sensor main body into
contact with the epithelial wall of the bladder.
SUMMARY
[0004] Studies are being conducted to predict a state of the
kidneys by measuring oxygen partial pressure in urine, assuming
that an oxygen status in urine reflects an oxygen status of kidney
tissue. In a case of predicting such a state of the kidneys, it is
important to measure an oxygen partial pressure in urine which has
just been excreted from the kidneys, that is, urine which is stably
flowing. However, by merely measuring and monitoring the oxygen
partial pressure in urine, it is not easy to confirm whether or not
the measured oxygen partial pressure is an oxygen partial pressure
in urine that is flowing stably.
[0005] The monitoring system and oxygen measurement system
disclosed here are able to confirm whether or not a measured oxygen
partial pressure is an oxygen partial pressure which is in urine
flowing stably and which appropriately reflects a state of the
kidneys is easy.
[0006] The monitoring system is connectable to an oxygen
measurement device that includes sensors to be exposed to urine
(urine obtained from a living body) and which operates to calculate
an oxygen partial pressure in urine and a flow rate of urine. The
monitoring system comprises: an oxygen partial pressure calculation
unit connected to a first one of the sensors of the oxygen
measurement device when the monitoring system is connected to the
oxygen measurement device to receive an output signal from the
first sensor and to calculate, for display on the monitor, an
oxygen partial pressure in the urine based on the output signal
from the first sensor of the oxygen measurement device. A flow rate
calculation unit is connected to a second one of the sensors of the
oxygen measurement device when the monitoring system is connected
to the oxygen measurement device to receive an output signal from
the second sensor and to calculate a flow rate of the urine based
on the output signal from the second sensor of the oxygen
measurement device. A display control unit is connected to a
monitor during operation of the monitoring system and controls a
format of a display of the oxygen partial pressure on the monitor
so that the format of the display of the oxygen partial pressure on
the monitor varies based on the calculated flow rate of urine, to
thereby allow a user of the monitoring system to confirm whether or
not the oxygen partial pressure is an oxygen partial pressure
acquired in a state that appropriately reflects a state of the
kidneys.
[0007] According to such a configuration, by looking at the format
of display of the oxygen partial pressure displayed on the monitor,
it is possible to easily confirm whether or not a measured oxygen
partial pressure is an oxygen partial pressure which is in urine
flowing stably and which appropriately reflects a state of the
kidneys.
[0008] The monitoring system further includes a flow rate
determination unit that determines whether or not the flow rate of
the urine acquired based on the output signal from the first sensor
of the oxygen measurement device is equal to or more than a
predetermined value. The display control unit controls the format
of the display of the oxygen partial pressure so that the oxygen
partial pressure is displayed on the monitor in a first display
format when the flow rate determination unit determines that the
flow rate of the urine is equal to or higher than the predetermined
value, and controls the format of the display of the oxygen partial
pressure so that the oxygen partial pressure is displayed on the
monitor in a second display format visually different from the
first display format when the flow rate determination unit
determines that the flow rate of the urine is less than the
predetermined value.
[0009] According to such a configuration, in a case where the
monitor displays the oxygen partial pressure in the first display
format, it is possible to easily confirm that the measured oxygen
partial pressure is an oxygen partial pressure in urine flowing at
a flow rate equal to or higher than a predetermined value. In
addition, in a case where the monitor displays the oxygen partial
pressure in the second display format, it is possible to easily
confirm that the measured oxygen partial pressure is an oxygen
partial pressure in urine at a flow rate less than a predetermined
value. Accordingly, it is possible to easily confirm whether or not
the oxygen partial pressure is an oxygen partial pressure which is
acquired in a state that appropriately reflects a state of the
kidneys.
[0010] The monitoring system further includes a flow rate
determination unit that determines whether or not the flow rate of
the urine acquired based on the output signal from the first sensor
of the oxygen measurement device is equal to or more than a
predetermined value. The display control unit controls the format
of the display of the oxygen partial pressure so that the oxygen
partial pressure is displayed on the monitor when the flow rate
determination unit determines that the flow rate of urine is equal
to or higher than the predetermined value, and controls the format
of the display of the oxygen partial pressure so that the oxygen
partial pressure is not displayed on the monitor when the flow rate
determination unit determines that the flow rate of urine is less
than the predetermined value.
[0011] According to such a configuration, in a case where the
monitor displays the oxygen partial pressure, it is possible to
easily confirm that the measured oxygen partial pressure is an
oxygen partial pressure in urine flowing at a flow rate equal to or
higher than a predetermined value. Accordingly, it is possible to
easily confirm whether or not the oxygen partial pressure is an
oxygen partial pressure which is acquired in a state that
appropriately reflects a state of the kidneys.
[0012] In the monitoring system, the display control unit may allow
the monitor to display a graph indicating a temporal change of
oxygen partial pressure.
[0013] According to such a configuration, it is possible to easily
confirm a temporal change of oxygen partial pressure in urine.
Accordingly, it is possible to easily confirm whether a state of
the kidneys is in better state as compared to the previous state,
and it is possible to perform interventions such as treatment and
its adjustment at appropriate timing as needed.
[0014] In the monitoring system, the oxygen partial pressure
calculation unit may calculate the oxygen partial pressure in urine
corrected by a temperature in the urine acquired based on the
output signal from a further sensor of the oxygen measurement
device.
[0015] According to such a configuration, it is possible to display
a more accurate oxygen partial pressure in urine which has been
temperature-corrected on the monitor.
[0016] The monitoring system further includes a urine volume
calculation unit connected to the second one of the sensors of the
oxygen measurement device when the monitoring system is connected
to the oxygen measurement device to receive an output signal from
the second sensor and to calculate, for display on the monitor, a
urine volume based on the output signal from the second sensor of
the oxygen measurement device. A urine volume determination unit
determines whether or not the urine volume calculated by the urine
volume calculation unit matches a predetermined urine volume
condition, and the display control unit displays the predetermined
urine volume condition on the monitor when the urine volume
determination unit determines that the urine volume matches the
urine volume condition.
[0017] According to such a configuration, it is possible to easily
confirm whether or not the urine volume matches a predetermined
urine volume condition (for example, whether or not the urine
volume is excessively small). Accordingly, it is possible to easily
confirm whether a state of the kidneys is in better state as
compared to the previous state, and it is possible to perform
interventions such as treatment and its adjustment at appropriate
timing as needed.
[0018] An oxygen measurement system comprises: a urethral catheter
that includes a urine flow lumen in which urine circulates; an
oxygen sensor that is mounted along the urine flow lumen in the
urethral catheter and that outputs an output signal used to
calculate an oxygen partial pressure in the urine circulating in
the urine flow lumen of the urethral catheter; a flow rate sensor
that is mounted along the urine flow lumen in the urethral catheter
and that outputs an output signal used to calculate a flow rate of
the urine circulating in the urine flow lumen of the urethral
catheter; an oxygen partial pressure calculation unit that
calculates the oxygen partial pressure in the urine circulating in
the urine flow lumen of the urethral catheter based on the output
signal output from the oxygen sensor; a flow rate calculation unit
that calculates a flow rate of the urine circulating in the urine
flow lumen of the urethral catheter based on the output signal
output from the flow rate sensor; a monitor that displays the
oxygen partial pressure calculated by the oxygen partial pressure
calculation unit; and a display control unit that is connected to
the monitor and that changes a format of a display of the oxygen
partial pressure on the monitor so that the format of the display
of the oxygen partial pressure on the monitor varies based on the
flow rate of the urine.
[0019] According to such a configuration, it is possible to obtain
an oxygen measurement system that exhibits the same effect as the
monitoring system described above.
[0020] According to another aspect, a method comprises positioning
a distal portion of an elongated urethral catheter in a bladder of
a living body, introducing urine from the bladder of the living
body into a lumen of the elongated urethral catheter; calculating
an oxygen partial pressure in the urine in the lumen of the
elongated urethral catheter based on an output signal of a first
sensor that is contacted by the urine in the lumen of the elongated
urethral catheter; calculating a flow rate of the urine in the
lumen of the elongated urethral catheter based on an output signal
from a second sensor that is contacted by the urine in the lumen of
the elongated urethral catheter; and controlling display of the
calculated oxygen partial pressure on the monitor, wherein the
controlling of the display of the calculated oxygen partial
pressure comprises varying a format of the display of the oxygen
partial pressure on the monitor based on the calculated flow rate
of the urine.
[0021] The monitoring system and method disclosed here are
implemented so that the format of display of an oxygen partial
pressure on a monitor is changed according to a flow rate of urine
acquired based on an output signal from an oxygen measurement
device, so that by looking at the format of display of the oxygen
partial pressure on the monitor, it is possible for the user to
easily confirm whether or not the measured oxygen partial pressure
is an oxygen partial pressure in urine flowing stably. Accordingly,
it is possible to easily confirm whether or not the oxygen partial
pressure is an oxygen partial pressure which is acquired in a state
that appropriately reflects a state of the kidneys. In addition, it
is possible to easily confirm whether a state of the kidneys is in
better state as compared to the previous state, and it is possible
to perform interventions such as treatment and its adjustment at
appropriate timing as needed.
BRIEF DESCRIPTION OF THE DRAWINGS
[0022] FIG. 1 is a schematic view showing a schematic configuration
of an oxygen measurement system including an oxygen measurement
device according to one disclosed embodiment.
[0023] FIG. 2 is a partially omitted longitudinal cross-sectional
view of the oxygen measurement device shown in FIG. 1.
[0024] FIG. 3 is a partially omitted longitudinal cross-sectional
view taken along the line III-III in FIG. 2.
[0025] FIG. 4 is a perspective view of a closing portion and an
oxygen sensor main body shown in FIG. 2.
[0026] FIG. 5 is a transverse cross-sectional view taken along the
line V-V of FIG. 3.
[0027] FIG. 6 is a block diagram illustrating a monitor main body
portion shown in FIG. 1.
[0028] FIG. 7 is a schematic view illustrating a method for using
the oxygen measurement system.
[0029] FIG. 8 is a first flow chart illustrating the method for
using the oxygen measurement system.
[0030] FIG. 9 is a second flow chart illustrating the method for
using the oxygen measurement system.
[0031] FIG. 10 is a first view showing measurement results of the
oxygen measurement system which are displayed on a monitor.
[0032] FIG. 11A is a second view showing measurement results of the
oxygen measurement system which are displayed on the monitor, and
FIG. 11B is a third view showing measurement results of the oxygen
measurement system which are displayed on the monitor.
[0033] FIG. 12 is a cross-sectional view showing a modification
example of an oxygen measurement device.
DETAILED DESCRIPTION
[0034] Set forth below with reference to the accompanying drawings
is a detailed description of embodiments of a monitoring system and
an oxygen measurement system representing examples of the inventive
monitoring system and an oxygen measurement system disclosed
here.
[0035] An oxygen measurement system 12 according to one embodiment
disclosed here by way of example is for measuring an oxygen partial
pressure (oxygen concentration) in urine excreted from kidneys into
a bladder 140 in order to predict or ascertain the condition of the
kidneys.
[0036] As shown in FIG. 1, the oxygen measurement system 12
includes an oxygen measurement device 10A comprised of a urethral
catheter 18, a urine collection bag 14 (a urine collection
container), and a monitoring system 16. In the following
description, the right side of the urethral catheter 18 in FIG. 2
is referred to as the "proximal side" (proximal end) and the left
side of the urethral catheter 18 is referred to as the "distal
side" (distal end). This same nomenclature applies to the other
drawings.
[0037] As shown in FIGS. 1 and 2, the oxygen measurement device 10A
includes a urethral catheter 18 and an oxygen sensor 20. The
urethral catheter 18 is a medical device that is indwelled in the
living body at the time of use and directs or conveys the urine in
the bladder 140 into the urine collection bag 14 disposed outside
the body. The urethral catheter 18 includes a flexible hollow
elongated shaft 22, a closing portion 23 (distal end cap) provided
at the distal end of the shaft 22, a balloon 24 provided at the
distal portion of the shaft 22, and a hub 26 provided at the
proximal portion of the shaft 22.
[0038] The shaft 22 is a thin and long tube. The shaft 22 has
adequate flexibility and adequate rigidity to allow the distal
portion of the urethral catheter 18 to pass smoothly into the
bladder 140 through a urethra 144. Examples of constituent
materials from which the shaft 22 may be fabricated include rubbers
such as silicone or latex, other elastomers, vinyl chloride,
polyurethane, plastic tubes, and the like.
[0039] As shown in FIGS. 2 and 3, the shaft 22 includes two
urethral catheter ports 28 (through holes in the wall of the shaft
22) which allow urine in the bladder 140 to flow into the shaft 22;
a lumen 30 communicating with the urethral catheter ports 28 and
extending the entire length of the shaft 22; and an inflation lumen
32 for circulating the inflation fluid of the balloon 24. The lumen
30 is surrounded by the wall constituting the elongated shaft
22.
[0040] Each of the urethral catheter ports 28 opens at a position
distal of the balloon 24 on the outer peripheral surface of the
shaft 22. The two urethral catheter ports 28 are provided at
positions facing each other (diametrically opposed). Each of the
urethral catheter port 28 is an elongated hole extending in the
longitudinal direction of the shaft 22 as generally shown in FIGS.
1-3. Specifically, each urethral catheter port 28 is formed in the
shape (shape close to an ellipse) in which each short side of the
rectangle protrudes outward in an arc shape (refer to FIG. 2). The
shape, size, position and number of the urethral catheter port 28
can be optionally set.
[0041] A distal end opening portion 34 of the lumen 30 is formed at
the distal end surface of the shaft 22. The distal end opening
portion 34 of the lumen 30 is closed by the closing portion 23. The
closing portion 23 may be made of the same material as the shaft
22. As shown in FIG. 2, FIG. 3, and FIG. 5, the closing portion 23
includes a distal end enlarged portion 36 that tapers in outer
dimension toward the distal end of the enlarged portion 36 (i.e.,
in a direction away from the shaft 22), and a protruding portion 38
that protrudes in the proximal direction from a proximal surface
36a (refer to FIG. 4) of the distal end enlarged portion 36 and
that is fluid-tightly fitted to the distal end opening portion 34
of the lumen 30. An outer surface of the distal end enlarged
portion 36 is configured as a partial curved surface of a spheroid.
The proximal surface 36a of the distal end enlarged portion 36 is a
flat shape. The protruding portion 38 possesses a rectangular
parallelepiped shape.
[0042] In FIG. 2 and FIG. 3, the closing portion 23 may be fixed to
the shaft 22 by an adhesive 40. The adhesive 40 may be injected
between the proximal surface 36a of the distal end enlarged portion
36, and the distal end surface of the shaft 22; and between the
protruding portion 38, and the wall surface constituting the distal
end opening portion 34 of the lumen 30. A latching groove 41 is
formed across the entire width on each of two side surfaces 38b
located on both sides in a height direction (short direction) of a
protruding end surface 38a of the protruding portion 38 (refer to
FIG. 4).
[0043] A portion of the lumen 30 of the shaft 22 that is proximal
of the closing portion 23 functions as a urethral catheterization
lumen 42. The urethral catheterization lumen 42 is provided such
that the axis Ax of the shaft 22 is located in the urethral
catheterization lumen. According to one embodiment, the urethral
catheterization lumen 42 has a square cross section (refer to FIG.
5). However, the cross section of the urethral catheterization
lumen 42 may adopt any shape.
[0044] As shown in FIG. 3, a temperature sensor 44 is embedded in
the wall of the shaft 22. The temperature sensor 44 has a
temperature sensor main body or sensor for detecting temperature 46
(temperature probe) for detecting the temperature in the bladder
140, and a temperature transmission unit 48 electrically connected
to the temperature sensor main body 46. The temperature sensor main
body 46 is at the same position as the urethral catheterization
port 28 in the axial direction of the shaft 22. That is, the
temperature sensor main body 46 is at the same axial position as
the urethral catheter ports 28, meaning the temperature sensor main
body 46 and the urethral catheter ports 28 axial overlap one
another as shown in FIG. 3. The temperature sensor main body 46
includes a thermocouple, a resistance temperature detector, or a
thermistor. The temperature sensor 44 can detect a temperature of
urine in the bladder 140. The temperature sensor main body 46 may
be at a position shifted from the urethral catheter port 28 in the
axial direction of the shaft 22 toward the distal side or the
proximal side. In addition, the temperature sensor main body 46 may
be disposed in the urethral catheterization lumen 42. In this case,
a temperature of the urine circulating in the urine flow lumen 74
can be accurately detected.
[0045] The oxygen sensor 20 is provided in the urethral
catheterization lumen 42. The oxygen sensor 20, which is configured
as a so-called fluorescent (optical) oxygen sensor 20, includes an
oxygen sensor main body 50, which is capable of detecting oxygen in
urine, and an oxygen transmission unit 52 (optical fiber 58)
provided separately from the oxygen sensor main body 50 and
disposed in the urethral catheterization lumen 42. The oxygen
sensor 20 is fixed to the urethral catheter 18 so that the oxygen
sensor main body 50 contacts urine circulating in the urethral
catheterization lumen.
[0046] The oxygen sensor main body 50 has a substrate 54 (base
part) and a phosphor 56 applied to substantially the entire surface
of one side of the substrate 54. The substrate 54 is made of a
material that can transmit excitation light from the optical fiber
58 and fluorescence from the phosphor 56. Such a substrate 54 is
made of, for example, glass or polyethylene. The substrate 54 has
the same width as the width of the protruding portion 38, and is
provided on the protruding portion 38 such that at least a part of
the phosphor 56 is located in the urethral catheterization lumen.
Specifically, the substrate 54 covers the protruding end surface
38a and the two side surfaces 38b of the protruding portion 38 in a
state of being bent in a substantially U-shape. Each end portion of
the substrate 54, in an extending direction of the substrate 54, is
bent and fitted in a respective one of the latching grooves 41.
[0047] The phosphor 56 is made of a material that emits
fluorescence when irradiated with the excitation light from the
optical fiber 58. Specifically, examples of the material
constituting the phosphor 56 include platinum porphyrin, ruthenium
complex, pyrene derivative, and the like. The phosphor 56 may be
provided with a coating for blocking disturbance light. However,
the phosphor 56 may not have such a coating.
[0048] The oxygen transmission unit 52 is the optical fiber 58
which is capable of irradiating the phosphor 56 with excitation
light and capable of receiving fluorescence from the phosphor 56.
The oxygen transmission unit 52 is fixed to the urethral catheter
18 with the position of the distal end surface 58a of the optical
fiber 58 fixed with respect to the phosphor 56. The optical fiber
58 may be a glass optical fiber or a plastic optical fiber. The
optical fiber 58 may be fixed to the shaft 22 by the fixing portion
60 such that the distal end surface 58a where the core is exposed
faces the phosphor 56 at a distance.
[0049] The fixing portion 60 includes a fiber support portion 64
that is provided on a wall surface of the urethral catheterization
lumen 42 (the wall surface surrounding the urethral catheterization
lumen 42) and that has an insertion hole 62 into which a distal
portion of the optical fiber 58 is inserted or positioned; and an
adhesive 66 for fixing the optical fiber 58 to the wall surface of
the urethral catheterization lumen 42. The adhesive 66 seals a
through-hole 68 formed on the outer surface of the shaft 22. The
adhesive 66 is made of a material that can transmit light from the
optical fiber 58 and fluorescence from the phosphor 56. For this
reason, even in a case where the adhesive 66 penetrates between the
distal end surface 58a of the optical fiber 58, and the substrate
54, the excitation light from the optical fiber 58 is applied to
the phosphor 56, and the fluorescence from the phosphor 56 can be
received by the optical fiber 58. A position of the distal end
surface 58a of the optical fiber 58 in an axial direction of the
shaft 22 is substantially the same as the position of the end
portion of the urethral catheter port 28 in a distal end
direction.
[0050] The balloon 24 can be inflated and contracted by changes in
internal pressure. That is, the balloon 24 is inflated by the
introduction of the inflation fluid into the balloon 24 and is
contracted by the inflation fluid being discharged from the balloon
24. FIG. 1 shows the balloon 24 in the inflated state.
[0051] The hub 26 is integrally formed in a hollow shape of a resin
material or the same material as that of the shaft 22. The hub 26
is provided with a urine port 70 in communication with the urethral
catheterization lumen 42 and a balloon inflation port 72 in
communication with the inflation lumen 32. The urethral
catheterization lumen 42 and the urine port 70 constitute a urine
flow lumen 74 as a urine drainage flow path of the urethral
catheter 18. A flow rate sensor 76 capable of detecting the flow
rate of urine circulating in the urine port 70 is provided on the
wall surface of the urine port 70. That is, the flow rate sensor 76
is positioned so that the flow rate sensor 76 contacts the urine
circulating in the urine port 70 or in the vicinity of the inside
of the wall. The balloon inflation port 72 is configured to be
connectable to a pressure application device (not shown) for
pumping the inflation fluid into the balloon 24 through the
inflation lumen 32. The balloon inflation port 72 also includes a
valve structure (not shown) that opens when the pressure
application device is connected and closes when it is separated.
The hub 26 is configured such that the cable connector 90 of the
monitoring system 16 is attachable and detachable.
[0052] As shown in FIG. 1, the urine collection bag 14 is
configured as a so-called closed bag, and includes a bag main body
78, the urethral catheter tube 80 for guiding urine in the urethral
catheter 18 into the bag main body 78, and a urine or discharge
portion 82 for discharging urine in the bag main body 78. Such a
urine collection bag 14 is integrally formed of a resin material or
the like. That is, the bag main body 78, the urethral catheter tube
80 and the discharge portion 82 may be integrally formed as one
piece. However, the urine collection bag 14 may be a separate
bag.
[0053] As shown in FIG. 1 and FIG. 2, the monitoring system 16
includes the cable connector 90 attachable to and detachable from
the hub 26, a long transmission cable 92 interlocked to the cable
connector 90, and a monitor main body portion 94 interlocked to the
transmission cable 92. The cable connector 90 is provided with an
oxygen cable 96 optically connected to the oxygen transmission unit
52; a temperature cable 98 electrically connected to the
temperature transmission unit 48; and a flow rate cable 100
electrically connected to the flow rate sensor 76. The oxygen cable
96 is an optical fiber, and the temperature cable 98 and the flow
rate cable 100 are electric wires. The oxygen cable 96, the
temperature cable 98, and the flow rate cable 100 are bundled
together by the transmission cable 92 and extend to the monitor
main body portion 94.
[0054] The transmission cable 92 is disposed along the urethral
catheter tube 80, and is locked to or fixed with respect to the
urethral catheter tube 80 by a plurality of latch sections 102
(banding bands). Accordingly, hindrance of the oxygen measurement
device 10A by the urethral catheter tube 80 and the transmission
cable 92 can be suppressed.
[0055] As shown in FIG. 6, the monitor main body portion 94
includes a light emitting section 104, a light receiving section
106, an A/D converter 108, a start button 110, a stop button 112, a
monitor 114, and a control unit 116.
[0056] The light emitting section 104 is, for example, a light
emitting diode, and emits excitation light of a predetermined
wavelength to the oxygen cable 96. The light receiving section 106
is, for example, a photodiode, and the fluorescence transmitted
from the oxygen cable 96 is incident. The A/D converter 108
converts the light reception signal of the light receiving section
106 into a digital value and outputs the digital value to the
control unit 116.
[0057] The start button 110 is a button for starting measurement of
an oxygen partial pressure in urine. The stop button 112 is a
button for stopping measurement of the oxygen partial pressure in
urine. The monitor main body portion 94 is also provided with a
power button (not shown) and the like.
[0058] The monitor 114 is configured to be able to display the
oxygen partial pressure in urine calculated by the control unit
116. The monitor 114 is a so-called full dot liquid crystal type
display, and can display predetermined information in color. The
monitor 114 has a touch panel function, and also functions as an
input unit for inputting predetermined information. As an input
format by the monitor 114, a pointing device such as a mouse cursor
type, a touch pen type, and a touch pad type can be used in
addition to the touch panel type. The input of information to the
monitor main body portion 94 is not limited to the input by the
monitor 114, and may be input by an input button or the like.
[0059] The control unit 116 includes a storage unit 118 and various
function implementation units. The function implementation unit is
a software function unit whose function is realized by the central
processing unit (CPU) executing a program stored in the storage
unit 118; however, it can be realized by a hardware functional unit
formed of an integrated circuit such as a Field-Programmable Gate
Array (FPGA). The storage unit 118 includes a writable non-volatile
memory (for example, a flash memory), and can store information
input via the monitor 114, information calculated by the control
unit 116, and the like.
[0060] The control unit 116 includes a storage unit 118, an oxygen
partial pressure calculation unit 120, a urine volume calculation
unit 122, a flow rate calculation unit 123, a flow rate
determination unit 124, a urine volume condition setting unit 126,
a urine volume determination unit 128, and a display control unit
130. The control unit 116 further includes a temperature input unit
(not shown) to which the output signal of the temperature sensor 44
is input, and a flow rate input unit (not shown) to which the
output signal of the flow rate sensor 76 is input.
[0061] The oxygen partial pressure calculation unit 120 calculates
the oxygen partial pressure in urine based on the output signal of
the oxygen sensor 20 and the output signal of the temperature
sensor 44. The urine volume calculation unit 122 calculates an
amount of urine based on the output signal of the flow rate sensor
76. The flow rate calculation unit 123 calculates the flow rate V
of the urine in the urine flow lumen 74 based on the output signal
from the flow rate sensor 76.
[0062] The urine volume condition setting unit 126 sets a
predetermined urine volume condition. Specifically, the urine
volume condition setting unit 126 sets the first urine volume
determination value and the second urine volume determination
value. The first urine volume determination value is calculated by
multiplying, for example, a first urine volume reference value (0.5
ml/kg/h) used for determination of the first stage and second stage
of acute kidney injury (AKI) by the weight of the patient. The
second urine volume determination value is calculated by
multiplying a second urine volume reference value (0.3 ml/kg/h)
used for determination of the third stage of acute kidney injury by
the weight of the patient. However, the urine volume condition
setting unit 126 can set any condition. The urine volume
determination unit 128 determines whether or not the urine volume
calculated by the urine volume calculation unit 122 matches a
predetermined urine volume condition.
[0063] The display control unit 130 changes the format of display
of the oxygen partial pressure on the monitor 114 according to the
flow rate V of urine acquired based on the output signal of the
flow rate sensor 76. Specifically, the display control unit 130
causes the monitor 114 to display the oxygen partial pressure in
the first display format when the flow rate determination unit 124
determines that the flow rate V of urine is equal to or higher than
a predetermined value (equal to or higher than a reference flow
rate V0), and causes the monitor 114 to display the oxygen partial
pressure in a second display format different from the first
display format when the flow rate determination unit 124 determines
that the flow rate V of urine is less than a predetermined value
(less than a reference flow rate V0). The display control unit 130
causes the monitor 114 to display a graph indicating temporal
changes in oxygen partial pressure. When the urine volume
determination unit 128 determines that the urine volume corresponds
to the urine volume condition, the display control unit 130 causes
the monitor 114 to display a message indicating the result.
[0064] Next, assembly of the oxygen sensor 20 to the urethral
catheter 18 will be described. In the present embodiment, the
optical fiber 58 is disposed in the urethral catheterization lumen
42, and the distal end of the optical fiber 58 is inserted into the
insertion hole 62 of the fiber support portion 64. Then, the
optical fiber 58 is fixed to the shaft 22 by injecting the adhesive
66 from the outside of the shaft 22 through the through-hole 68. In
addition, in a state where the substrate 54 of the oxygen sensor
main body 50 is bent in a U-shape, the end portions of the
substrate 54 are each locked in a respective one of the latching
grooves 41 of the protruding portion 38. Furthermore, with the
adhesive 66 applied to the distal end surface of the shaft 22 and
the wall surface of the distal end opening portion 34, the closing
portion 23 holding the oxygen sensor main body 50 is fitted to the
distal end opening portion 34 of the shaft 22. Then, the closing
portion 23 is fixed to the shaft 22, and the oxygen sensor main
body 50 is fixed to the shaft 22. Accordingly, the phosphor 56 and
the distal end surface 58a of the optical fiber 58 can be
positioned with high accuracy.
[0065] A use of the oxygen measurement device 10A will now be
described.
[0066] As shown in FIGS. 7 and 8, first, the preparation process is
performed (step S1 in FIG. 8). In the preparation step, the tip or
distal portion of the urethral catheter 18 is indwelled in the
bladder 140. Specifically, the distal end of the shaft 22 coated
with lubricating jelly is inserted into the urethra 144 from the
urethral orifice 142 of the patient, and the distal end of the
shaft 22 is advanced to position the urethral catheter port 28 and
the balloon 24 in the bladder 140. The urethral catheter 18 may be
easily inserted into the bladder 140 by inserting a stylet (not
shown) into the urethral catheterization lumen 42 in the shaft 22
to impart sufficient rigidity to the shaft 22.
[0067] Thereafter, the balloon 24 is inflated by pumping the
inflation fluid from a pressure application device (not shown) from
the inflation port to the inflation lumen 32 (refer to FIG. 2).
Accordingly, the urethral catheter 18 is prevented from coming out
of the body, and a distal portion of the shaft 22 that is distal of
the balloon 24 is indwelled in the bladder 140. Reference numeral
146 in FIG. 7 is a pubic bone, reference numeral 148 is a prostate,
and reference numeral 150 is an external urinary sphincter.
[0068] When the distal portion of the urethral catheter 18 is
indwelled in the bladder 140, the urine in the bladder 140 can be
excreted via the urethral catheter 18 into the urine collection bag
14. At this time, in the urethral catheter 18, urine in the bladder
140 flows into the urine flow lumen 74 by way of the urethral
catheter port 28.
[0069] In addition, the user inputs the weight of the patient into
the monitor main body portion 94 (step S2). Then, the urine volume
condition setting unit 126 calculates the first urine volume
determination value and the second urine volume determination value
based on the input patient weight (step S3).
[0070] Thereafter, the user operates the start button 110 (step
S4). Accordingly, measurement of the oxygen partial pressure in
urine is started. When the start button 110 is operated,
measurement of the oxygen partial pressure in urine is performed
continuously or intermittently (for example, every 5 minutes) until
the stop button 112 is operated.
[0071] Specifically, the control unit 116 acquires various data
(step S5). In other words, the control unit 116 acquires the output
signal of the temperature sensor 44 and the output signal of the
flow rate sensor 76. Furthermore, the control unit 116 controls the
light emitting section 104 to emit excitation light of a
predetermined wavelength. Then, the excitation light emitted from
the light emitting section 104 is transmitted to the optical fiber
58 through the oxygen cable 96, and the phosphor 56 of the oxygen
sensor main body 50 is irradiated therewith from the distal end
surface 58a of the optical fiber 58. The phosphor 56 irradiated
with excitation light transitions from the ground state to the
excited state, and returns to the ground state while emitting
fluorescence. At this time, when oxygen molecules exist around the
phosphor 56, the interaction deprives the excitation energy to
oxygen molecules, and the intensity of fluorescence emission
decreases. This phenomenon is called a quenching phenomenon, and
the intensity of fluorescence emission is inversely proportional to
an oxygen molecule concentration. The fluorescence of the phosphor
56 is incident from the distal end surface 58a of the optical fiber
58 and is guided to the light receiving section 106 through the
optical fiber 58 and the cable 96 for oxygen. The light reception
signal of the light receiving section 106 is converted into a
digital signal by the A/D converter 108 and input to the control
unit 116. Accordingly, the output signal of the oxygen sensor 20 is
acquired.
[0072] Thereafter, the oxygen partial pressure calculation unit 120
calculates the oxygen partial pressure in urine based on the output
signal of the oxygen sensor 20 (the output signal of the A/D
converter 108) and the output signal of the temperature sensor 44
(step S6). In addition, the flow rate determination unit 124
determines whether or not the flow rate V of urine acquired is
equal to or higher than a predetermined value (reference flow rate
V0) based on the output signal of the flow rate sensor 76 (step
S7). The reference flow rate V0 is stored in advance in the storage
unit 118.
[0073] When the flow rate determination unit 124 determines that
the flow rate V is equal to or higher than the reference flow rate
V0 (step S7: YES), the display control unit 130 performs setting so
that the calculated oxygen partial pressure is displayed on the
monitor 114 in the first display format (step S8). On the other
hand, when the flow rate determination unit 124 determines that the
flow rate V is less than the reference flow rate V0 (step S7: NO),
the display control unit 130 performs setting so that the
calculated oxygen partial pressure is displayed on the monitor 114
in the second display format (step S9).
[0074] Subsequently, urine volume determination control (step S10)
is performed. In the urine volume determination control (step S10),
the urine volume calculation unit 122 first calculates the urine
volume and its integrated value (step S20 in FIG. 9). In other
words, the urine volume calculation unit 122 calculates an amount
of urine based on the output signal of the flow rate sensor 76. The
calculated urine volume is stored in the storage unit 118. Then,
the urine volume calculation unit 122 calculates the integrated
value of the urine volume by adding the urine volume calculated in
the present measurement to the urine volume stored in the storage
unit 118. The integrated value of the urine volume is stored in the
storage unit 118.
[0075] Thereafter, the urine volume calculation unit 122 calculates
the urine volume per unit time (for example, per hour) based on the
integrated value of the urine volume (step S21). Subsequently, the
urine volume determination unit 128 determines whether or not the
urine volume per unit time matches the urine volume condition (step
S22).
[0076] Specifically, the urine volume determination unit 128
determines whether or not the urine volume per unit time
corresponds to any one of the first to third stages of AKI. More
specifically, the urine volume determination unit 128 determines
that the urine volume per unit time corresponds to the first stage
when the urine volume per unit time remains less than the first
urine volume determination value for six hours or more. In
addition, the urine volume determination unit 128 determines that
the urine volume per unit time corresponds to the second stage when
the urine volume per unit time remains less than the first urine
volume determination value for 12 hours or more. Furthermore, the
urine volume determination unit 128 determines that the urine
volume per unit time corresponds to the third stage when the urine
volume per unit time remains less than the second urine volume
determination value for 24 hours or more or when no urine volume
remains for 12 hours or more.
[0077] When the urine volume determination unit 128 determines that
the urine volume per unit time corresponds to any one of the first
to third stages of AKI (step S22: YES), the display control unit
130 causes the monitor 114 to display a message indicating that the
urine volume per unit time corresponds to the urine volume
condition (any one of the first to third stages) (step S23), and
causes the process to proceed to the step S11 in FIG. 8. On the
other hand, when the urine volume determination unit 128 determines
that the urine volume per unit time does not correspond to any of
the first to third stages of AKI (step S22: NO), the display
control unit 130 causes the process to proceed to the step S11 in
FIG. 8.
[0078] Thereafter, in step S11, the display control unit 130 causes
the monitor 114 to display various pieces of information.
Specifically, as shown in FIG. 10, the display control unit 130
causes the monitor 114 to numerically display, for example, the
oxygen partial pressure, the temperature in the bladder 140, the
urine volume, and the integrated value of the urine volume, and
causes the monitor 114 to display temporal changes in oxygen
partial pressure and temporal changes in the temperature in the
bladder 140 in the form of a graph. In addition, when the urine
volume determination control determines that the urine volume per
unit time corresponds to any one of the first to third stages of
AKI (step S22: YES), the display control unit 130 causes the
monitor 114 to display a message indicating the result. The display
control unit 130 does not cause the monitor 114 to display the AKI
when the urine volume determination control determines that the
urine volume per unit time does not correspond to any of the first
to third stages of AKI (step S22: NO).
[0079] In the example of FIG. 10, the oxygen partial pressure of 38
mmHg, the temperature in the bladder 140 of 37.4.degree. C., the
urine volume per unit time of 25.1 mL/h, the cumulative volume of
urine of 532 mL, and AKI being the first stage are displayed. In
addition, the temporal changes in oxygen partial pressure are
displayed in the form of a bar graph, and the temporal changes in
the temperature in the bladder 140 are displayed in the form of a
line graph. That is, the horizontal axis represents time, one
vertical axis represents oxygen partial pressure (mmHg), and the
other vertical axis represents temperature (.degree. C.).
Furthermore, in the bar graph, the filled portion is a portion
displaying the oxygen partial pressure in the first display format,
and the non-filled portion is a portion displaying the oxygen
partial pressure in the second display format. As shown in FIG. 10,
the first display format and the second display format are visually
distinguishable formats. In other words, in the bar graph, the
oxygen partial pressure in the filled portion is the oxygen partial
pressure in urine when the flow rate V of urine is equal to or
higher than the reference flow rate V0, the oxygen partial pressure
in the unfilled part is the oxygen partial pressure in urine when
the flow rate V of urine is less than the reference flow rate
V0.
[0080] The first display format and the second display format of
the oxygen partial pressure are not limited to the example of FIG.
10. For example, in the bar graph, the first display format may be
displayed in a non-filled state, and the second display format may
be displayed in a filled state.
[0081] In addition, as shown in FIG. 11A, the display control unit
130 may cause the monitor 114 to display a temporal change in
oxygen partial pressure as a line graph. In this case, in the line
graph, a thick line portion indicates the oxygen partial pressure
in the first display format, and a thin line portion indicates the
oxygen partial pressure in the second display format. However, this
can be varied, for example the first display format may be
displayed as a thin line, and the second display format may be
displayed as a thick line.
[0082] In addition, as shown in FIG. 11B, in the line graph, a
portion in which the lower side of the line segment indicating the
value of the oxygen partial pressure is filled may be taken as the
first display format of the oxygen partial pressure, and a portion
in which the lower side is not filled up may be taken as the second
display format of the oxygen partial pressure. However, the first
display format may be displayed in a state in which the lower side
is a not filled, and the second display format may be displayed in
a state in which the lower side is a filled.
[0083] Thereafter, the control unit 116 determines whether or not
the stop button 112 is operated (step S12). In a case where the
stop button 112 has not been operated (step S12: NO), the processes
after step S5 are performed. On the other hand, in a case where the
stop button 112 is operated (step S12: YES), the control unit 116
stops the operation of the oxygen measurement. In other words, the
light emission of excitation light of the light emitting section
104 is stopped. At this stage, the oxygen measurement process of
the present flowchart ends.
[0084] Next, effects of the present embodiment will be
described.
[0085] The monitoring system 16 is connected to the oxygen
measurement device 10A capable of detecting an oxygen partial
pressure of urine and flow of urine in the urine flow lumen 74 of
the urethral catheter 18. The monitoring system 16 includes an
oxygen partial pressure calculation unit 120 that calculates an
oxygen partial pressure in urine based on an output signal from the
oxygen measurement device 10A (oxygen sensor 20); a monitor 114
that displays the oxygen partial pressure calculated by the oxygen
partial pressure calculation unit 120; and a display control unit
130 that changes the format of display of the oxygen partial
pressure on the monitor 114 according to the flow rate V of urine
acquired based on the output signal from the oxygen measurement
device 10A (flow rate sensor 76).
[0086] Accordingly, by looking at the format of display of the
oxygen partial pressure on the monitor 114, it is possible to
easily confirm whether or not a measured oxygen partial pressure is
an oxygen partial pressure which is in urine flowing stably and
which appropriately reflects a state of the kidneys.
[0087] The monitoring system 16 includes a flow rate determination
unit 124 that determines whether or not the flow rate V of urine
acquired is equal to or higher than a predetermined value (equal to
or higher than a reference flow rate V0). The display control unit
130 displays the oxygen partial pressure on the monitor 114 in the
first display format in a case where the flow rate determination
unit 124 determines that the flow rate V of urine is equal to or
higher than a predetermined value, and displays the oxygen partial
pressure on the monitor 114 in a second display format different
from the first display format in a case where the flow rate
determination unit 124 determines that the flow rate V of urine is
less than a predetermined value. Accordingly, in a case where the
monitor 114 displays the oxygen partial pressure in the first
display format, it is possible to easily confirm that the measured
oxygen partial pressure is an oxygen partial pressure in urine
flowing at a flow rate equal to or higher than a reference flow
rate V0. In addition, in a case where the monitor 114 displays the
oxygen partial pressure in the second display format, it is
possible to easily confirm that the measured oxygen partial
pressure is an oxygen partial pressure in urine at a flow rate less
than a reference flow rate V0. Accordingly, it is possible to
easily confirm whether or not the oxygen partial pressure is an
oxygen partial pressure which is acquired in a state that
appropriately reflects a state of the kidneys.
[0088] The display control unit 130 causes the monitor 114 to
display a graph indicating temporal change in oxygen partial
pressure. For this reason, it is possible to more easily confirm
whether or not the measured oxygen partial pressure is an oxygen
partial pressure in urine flowing at a flow rate equal to or higher
than a predetermined value. Accordingly, it is possible to easily
confirm whether a state of the kidneys is in better state as
compared to the previous state, and it is possible to perform
interventions such as treatment and its adjustment at appropriate
timing as needed.
[0089] The oxygen partial pressure calculation unit 120 calculates
the oxygen partial pressure in urine corrected by a temperature in
the urine acquired based on the output signal from the oxygen
measurement device 10A (temperature sensor 44). Accordingly, it is
possible to display a more accurate oxygen partial pressure in
urine which has been temperature-corrected on the monitor 114.
[0090] The monitoring system 16 includes a urine volume calculation
unit 122 that calculates a urine volume circulating in the urine
flow lumen based on the output signal from the oxygen measurement
device 10A (flow rate sensor 76); and a urine volume determination
unit 128 that determines whether or not the urine volume calculated
by the urine volume calculation unit 122 matches a predetermined
urine volume condition. When the urine volume determination unit
128 determines that the urine volume corresponds to the urine
volume condition, the display control unit 130 causes the monitor
114 to display a message indicating the result. Accordingly, it is
possible to easily confirm whether or not the urine volume matches
a predetermined urine volume condition (for example, whether or not
the urine volume is excessively small). Therefore, it is possible
to easily confirm whether a state of the kidneys is in better state
as compared to the previous state, and it is possible to perform
interventions such as treatment and its adjustment at appropriate
timing as needed.
[0091] In the monitoring system 16, the display control unit 130
may be configured to display the oxygen partial pressure on the
monitor 114 in a case where the flow rate determination unit 124
determines that the flow rate V of urine is equal to or higher than
a predetermined value, and not to display the oxygen partial
pressure on the monitor 114 in a case where the flow rate
determination unit 124 determines that the flow rate V of urine is
less than a predetermined value. Accordingly, in a case where the
monitor 114 displays the oxygen partial pressure, it is possible to
easily confirm that the measured oxygen partial pressure is an
oxygen partial pressure in urine flowing at a flow rate equal to or
higher than a predetermined value. Accordingly, it is possible to
easily confirm or identify whether or not the oxygen partial
pressure is an oxygen partial pressure which is acquired in a state
that appropriately reflects a state of the kidneys.
[0092] The monitoring system 16 may be connectable to the oxygen
measurement device 10A capable of detecting an oxygen partial
pressure of urine and flow of urine in the bladder 140 and flowing
outside the urethral catheter 18.
[0093] Next, an oxygen measurement device 10B according to a
modification example will be described. In the oxygen measurement
device 10B according to the modification example, the features or
components that are the same as those of the above-described oxygen
measurement device 10A are denoted by the same reference numerals,
and a detailed description of such features or components is not
repeated.
[0094] As shown in FIG. 12, the urethral catheter 18a of the oxygen
measurement device 10B according to the modification example
includes a hub 26a. The hub 26a comprises a hollow hub main body
600 provided at the proximal end of the shaft 22, and a hollow
interlock portion 602 provided at the proximal end of the hub main
body 600. The hub main body 600 is integrally formed (monolithic
structure) of resin material. In FIG. 12, the hub main body 600 has
a first urine lumen 604 in communication with the urethral
catheterization lumen 42, a balloon inflation port 72 in
communication with the inflation lumen 32, and a lead-out port 606
for leading out the proximal portion of the temperature
transmission unit 48 to the outside. The balloon inflation port 72
is configured to be connectable to a pressure application device
(not shown) for pumping the inflation fluid into the balloon 24
through the inflation lumen 32.
[0095] The interlock portion 602 is integrally formed (monolithic
structure) in a tubular shape by a resin material having
transparency (transparent resin material). The interlock portion
602 includes a first connection section 608 fitted into the
proximal end opening portion of the hub main body 600, an interlock
portion main body 610 provided at the proximal end of the first
connection section 608, and a second connection section 612
provided at the proximal portion of the interlock portion main body
610 and fitted into the distal end opening portion of a urethral
catheter tube 80 of the urine collection bag 14. As shown in FIG.
12, the first connection section 608 is at the distal end of the
interlock portion 602, and the second connection section 612 is at
the proximal end of the interlock portion 602.
[0096] The outer surface of the first connection section 608 is in
fluid tight contact with the inner surface of the proximal end
opening portion of the hub main body 600 by providing a plurality
of annular protrusion portions 614 on the outer surface of the
first connection section 608 in the axial direction that engage
similarly configured portions on the inner surface of the proximal
end opening portion of the hub main body 600. A second urine lumen
616 communicating with the first urine lumen 604 is formed in the
first connection section 608 and the interlock portion main body
610. Hereinafter, the first urine lumen 604 and the second urine
lumen 616 may be collectively referred to as a urine lumen 618. The
urine port 618 constitutes the urine flow lumen 74a of the urethral
catheter 18a. The cross-sectional shapes of the urethral
catheterization lumen 42 and the urine lumen 618 may be formed
identical (for example, rectangular) to each other. That is, the
flow path cross-sectional areas of the urethral catheterization
lumen 42 and the urine lumen 618 may be identical to each other.
Accordingly, it is possible to suppress the occurrence of
disturbance in the urine flowing from the urethral catheterization
lumen 42 to the urine lumen 618, and therefore it is possible to
circulate the urine smoothly.
[0097] The second connection section 612 includes an annular
protruding portion 620 protruding outward (radially outward) from
the interlock portion 602 and an extension portion 622 extending in
the proximal (axial) direction from the annular protruding portion
620. The flow path cross-sectional area of the lumen 624 of the
second connection section 612 is larger than the flow path
cross-sectional area of the second urine lumen 616. A plurality of
annular protrusion portions 626 are provided in the axial direction
on the outer surface of the extension portion 622 so that the outer
surface of the extension portion 622 is in fluid tight contact with
the inner surface of the distal end opening portion of the urethral
catheter tube 80. The proximal portion of the interlock portion
main body 610 protrudes into the lumen 624 of the second connection
section 612. The flow path cross-sectional area of the proximal
side opening portion of the protruding portion 628 (inflow
suppressing portion) which protrudes into the lumen 624 of the
second connection section 612 in the interlock portion main body
610 is smaller than flow path cross-sectional area of the lumen 624
of the second connection section 612. That is, because of surface
tension, the urine can come into contact with the wall surface
constituting the proximal end opening portion of the protruding
portion 628, so that air can be prevented from flowing from the
lumen 624 of the second connection section 62 while urine can be
prevented from flowing into the second urine lumen 616.
[0098] In the interlock portion main body 610, a port portion 632
for introducing a predetermined fluid into the second urine lumen
616, a support wall portion 634 located on the proximal side of the
port portion 632, an oxygen sensor main body 636 constituting the
oxygen sensor 660 for detecting oxygen in urine in the second urine
lumen 616, a temperature sensor main body 638 constituting the
temperature sensor 662 for detecting the temperature of urine in
the second urine lumen 616, and a flow rate sensor main body 640
constituting the flow rate sensor 664 for detecting the flow rate
of urine in the second urine lumen 616 are provided.
[0099] The port portion 632 is distal of the oxygen sensor main
body or sensor for detecting oxygen in urine 636, and includes a
valve body support portion 646 having a hole 644 in which a valve
body 642 is disposed. The valve body 642 is formed of an elastic
member 654 such as rubber, and for example, a hollow needle body of
the syringe (not shown) is configured to be able to puncture in a
fluid tight manner. The port portion 632 may function as a urine
collection port portion for collecting urine in the second urine
lumen 616.
[0100] Fixing holes 650a and 650b for fixing a cable connector 90
of the monitoring system 16 are formed in each of a surface of the
support wall portion 634 that faces the proximal direction and a
surface facing the tip (distal) direction of the annular protruding
portion 620. The oxygen sensor main body 636, the temperature
sensor main body 638, and the flow rate sensor main body 640 are
arranged in a row in this order from the distal side between the
support wall portion 634 and the protruding portion 628 in a
mutually separated manner. That is, the sensor that detects oxygen
in urine 636, the sensor that detects urine temperature 638 and the
sensor that detects urine flow rate 640 are arranged axially one
after another in an axially spaced apart manner, with the sensor
that detects urine temperature 638 being positioned axially between
the sensor that detects oxygen in urine 636 and the sensor that
detects urine flow rate 640, whereby the sensor that detects oxygen
in urine 636 is distal of the sensor that detects urine temperature
638, and the sensor that detects urine flow rate 640 is proximal of
the sensor that detects urine temperature 638 as shown in FIG.
12.
[0101] The oxygen sensor main body 636 is proximal of the port
portion 632 and distal of the temperature sensor main body 638 and
the flow rate sensor main body 640, and has a base part 656 having
a substrate 652 and an elastic portion 654, and a phosphor 658
provided on the base part or support 656. The phosphor 658 is
applied to the surface of the substrate 652 so as to contact the
urine in the second urine lumen 616. The elastic portion 654 is
provided on the back surface of the substrate 652 opposite to the
phosphor 658. Each of the substrate 652 and the elastic portion 654
is made of a transparent material. The substrate 652 and the
phosphor 658 are configured in the same manner as the substrate 54
and the phosphor 56 described above. The elastic portion 654 is
made of a flexible resin material such as rubber. The phosphor 658
has a larger area than the distal end surface of the oxygen cable
96 to be described later.
[0102] The temperature sensor main body 638 is proximal of the
oxygen sensor main body 636 and distal of the flow rate sensor main
body 640. In other words, the temperature sensor main body 638 is
located near the oxygen sensor main body 636. The temperature
sensor main body 638 is configured as a metal plate. The metal
plate is preferably made of, for example, a material having a high
thermal conductivity such as silver, copper, gold, stainless steel,
or aluminum. In this case, a temperature of the temperature sensor
main body 638 can be made substantially the same as a temperature
of the urine in the second urine lumen 616. However, when the
temperature sensor main body 638 can approximate a temperature of
the temperature sensor main body 638 to a temperature of urine in
the second urine lumen 616, the temperature sensor main body 638
may be a thin plate made from a material other than metal such as
resin material. The flow rate sensor main body 640 is proximal of
the temperature sensor main body 638, and is configured as, for
example, a Karman vortex type or thermal flow rate sensor 664.
[0103] The cable connector 90 includes a housing 91, and in the
housing 91, the oxygen cable 96 as an optical fiber optically
connectable to the oxygen sensor main body 636, a temperature
detection unit 97 which can contact or approach the temperature
sensor main body 638, a temperature cable 98 electrically
connectable to the temperature detection unit 97, and a flow rate
cable 100 electrically connectable to flow rate sensor main body
640 are provided.
[0104] The cable connector 90 is attachable to and detachable from
the hub 26a in a direction intersecting (orthogonal to) the axis of
the hub 26a. The housing 91 is provided with a pin 93a that can be
inserted into the fixing hole 650a and a pin 93b that can be
inserted into the fixing hole 650b. By operating an operation
portion (not shown) provided on the housing 91, each of the pins
93a and 93b is configured to be displaceable at a lock position
which protrudes outward of the housing 91 and can be inserted into
each of fixing holes 650a and 650b, and a withdrawing position
retracted inside the housing 91 and withdrawn from the fixing holes
650a and 650b. The housing 91 is provided with a connection
terminal 95 to which the terminal 49 provided at the proximal end
of the temperature transmission unit 48 can be electrically
connected. A cable (not shown) is electrically connected to the
connection terminal 95.
[0105] The control unit 116 further includes a temperature input
unit (not shown) to which the output signal of the temperature
sensor 662 is input, and a flow rate input unit (not shown) to
which the output signal of the flow rate sensor 664 is input.
[0106] In the case of this oxygen measurement device 10B according
to the modification example, the same effects as in the case of the
oxygen measurement device 10A described above can be acquired.
[0107] The oxygen measurement devices 10A and 10B may include a
pressure sensor that measures the pressure near the distal end of
the urethral catheter 18, 18a. The pressure sensor outputs an
electrical or optical signal to the monitoring system 16.
[0108] The monitor main body portion 94 may be configured to be
able to acquire time, atmospheric pressure around the monitor main
body portion 94, humidity around the monitor main body portion 94,
and temperature around the monitor main body portion 94. The time
includes the current time and an elapsed time from a certain
timing. The monitor main body portion 94 can be configured to be
able to read and reflect a calibration value at a unique initial
period (at the time of manufacture) of each sensor. Regarding a
method of inputting the calibration value, it may be input by
scanning a one-dimensional or two-dimensional barcode or may be
input directly from the monitor 114. Alternatively, the calibration
value may be held at a signal output unit of the urethral catheter
18 or 18a and automatically read by connecting the monitoring
system 16 to the urethral catheter 18 or 18a.
[0109] In the oxygen measurement system 12, operation confirmation
may be performed before use. In this case, it is confirmed that an
output value from each sensor of the oxygen measurement device 10A
or 10B is within the normal operation range. Specifically, a
reference value calculated from the temperature, humidity, and
atmospheric pressure around the monitor main body portion 94 is
compared with an output value from each sensor of the oxygen
measurement device 10A or 10B. Then, the control unit 116 of the
monitor main body portion 94 determines whether or not the output
value from each sensor of the oxygen measurement device 10A or 10B
is within the normal range, and reports the determination results.
In addition, whether or not the output value from each sensor of
the oxygen measurement device 10A or 10B is within the normal range
may be confirmed by acquiring the output value of each sensor using
a reference solution or reference gas, and comparing the output
value with the reference value.
[0110] The monitor main body portion 94 may notify various physical
quantities (oxygen partial pressure, temperature in the bladder
140, urine volume, and the like) based on the output values from
the sensors of the oxygen measurement device 10A or 10B.
Specifically, the monitor main body portion 94 can notify the
physical quantity by a numerical value, bar graph, dial gauge,
level meter, color or the like. In addition, the monitor main body
portion 94 can display the transition of the physical quantity on
the monitor 114 by the up and down arrows, various graphs (such as
line graphs), color change progress display, and the like.
[0111] There is a time lag before changes in the bladder 140 appear
as changes in urine flow rate in the oxygen measurement device 10A
or 10B. For this reason, the monitor main body portion 94 may
display a delay time until the change in the bladder 140 appears as
the output value of each sensor of the oxygen measurement device
10A or 10B on the monitor 114.
[0112] The monitor main body portion 94 allows the user to set
predetermined conditions. The monitor main body portion 94 may
determine and notify whether or not a state in which the setting
condition is satisfied has elapsed for a set time. That is, for
example, in a case where urine of the set urine volume cannot be
acquired, the monitor main body portion 94 may notify when a state
where setting conditions are satisfied (the low output state of the
sensor, the state where the temperature in the bladder 140 is lower
than the setting temperature, and the like) continues for the set
time or more.
[0113] The monitor main body portion 94 may determine and notify
that the set change has occurred. That is, for example, the monitor
main body portion 94 may notify when the rate of change in the flow
rate of urine exceeds the set rate of change or when the range of
change in the measured temperature of urine exceeds the set range
of change.
[0114] The monitor main body portion 94 may have a function of
maintaining the program inside, and may be configured to be able to
update the program by receiving update information from the
outside. In this case, the monitor main body portion 94 may receive
the update information by wireless connection or wired connection
(USB connection) with respect to the update information supply
source. In addition, the monitor main body portion 94 may receive
update information by replacing the memory card.
[0115] The monitor main body portion 94 may be configured to easily
operate necessary functions. That is, the monitor main body portion
94 may be configured to have at least one physical function key and
to freely assign functions to each function key. For example, the
monitor main body portion 94 may be configured to be able to
perform retroactive operation on past data by performing a dial
operation or a slide operation of the monitor 114 (screen).
[0116] The monitor main body portion 94 may be configured to be
able to print data in a selected range from an external printer or
the like.
[0117] The monitor main body portion 94 may be configured to be
able to divide a display area of the monitor 114 and display any
data in each display area. In this case, for example, current data
and past data can be easily compared. The monitor main body portion
94 may be configured to be able to output and display the display
of the monitor 114 on an external display apparatus.
[0118] The monitor main body portion 94 may be configured to
estimate a range of a urine volume from an infusion volume, and, at
the same time, to compare the estimated range and an actual urine
volume; to determine whether or not the urine volume range is
within the estimated range; and to report the determination
results. The infusion volume may be acquired by automatically
obtaining infusion data from an infusion pump, or may be acquired
by directly inputting the infusion volume.
[0119] The detailed description above describes embodiments of a
monitoring system and an oxygen measurement system representing
examples of the inventive monitoring system and an oxygen
measurement system disclosed here. The invention is not limited,
however, to the precise embodiments and variations described.
Various changes, modifications and equivalents can be effected by
one skilled in the art without departing from the spirit and scope
of the invention as defined in the accompanying claims. It is
expressly intended that all such changes, modifications and
equivalents which fall within the scope of the claims are embraced
by the claims.
* * * * *